Formation And Evolution Of Ordovician Reservoirs In The Bamai Region Area,Tarim Basin

This paper based on the geological and geophysical data,on the basis of the difference of hydrocarbon source rocks,regional caprock and fracture activity in the Cambrian area of the Cambrian area in the area,the history of single well sedimentary burial,thermal evolution and tectonic evolution are analyzed,and the formation process of regional oil and gas reservoirs is deeply discussed.Through the anatomic and comparative analysis of three oil and gas reservoirs in Yubei 1,Bashi 5 and Hetian River,which have been discovered in the Ordovician system,the difference of the reservoir characteristics of known oil and gas reservoirs is systematically studied.The relationship between different oil and gas reservoirs is clarified,and the main controlling factors of the Ordovician hydrocarbon accumulation are clarified,and the control effect of structural evolution on the Ordovician oil and gas reservoirs is revealed.The Ordovician system in the bar area has been found that oil and gas from the oil and gas reservoirs are derived from the Cambrian hydrocarbon source rocks of the Mengaiti slope,and the regional caprock is the Carboniferous Bachu formation mudstone section,which has experienced a multistage fracture activity.The early formation of oil and gas reservoirs have experienced damage and adjustment,and the accumulation process of oil and gas reservoirs has been found to be distinctly different.The main reservoir formation period of the reservoir and the 5 gas reservoir of Tian He gas reservoir and Ba exploration reservoir is late Hercynian and late Himalayan.The 1reservoir in Yubei has experienced the process of late Caledonian reservoir formation destruction-late Himalayan accumulation and late Himalayan adjustment.The difference of tectonic evolution is the key to different structural styles,effective cap rocks and oil and gas distribution characteristics of different reservoirs.The formation and evolution of the Ordovician oil and gas reservoirs in the area are controlled by the combination ofthe distribution and depth of the source rocks,the distribution of the effective cover,the period of fracture formation and its style.